The study was led by Nora D. Volkow, director of the National Institute on Drug Abuse, who cautions that it is premature to draw "clinical significance" to the findings. That means it is too early to say the findings mean cellphones could lead to bodily harm, including brain cancer.

"The brain is very important and if you ask what my recommendation is from this study, I'd say I can't overall say this is harmful but we have to study more for long-term effects," Volkow said in an interview.

Specifically her research shows that those people exposed to 50 minutes of cellphone radio frequencies saw an increased brain glucose metabolism in the region closest to the antenna.

"The dramatic increase in use of cellular telephones has generated concern about possible negative effects of radiofrequency signals delivered to the brain," JAMA wrote in background material on the study's release. "However, whether acute cellphone exposure affects the human brain is unclear."

Trade group CTIA-The Wireless Association has fought against local rules that would require labeling of radio-frequency levels at San Francisco retailers. The trade group filed a lawsuit against San Francisco and has sent lobbyists to Maine, California and Oregon to fight similar legilsations.

It has deferred to the Federal Communications Commission and Food and Drug Administrations as the expert agencies to oversee cellphone health. But public-interest groups say the regulatory agencies haven't updated guidelines on cellphone health in more than one decade. And the rapid adoption of cellphones -- 290 million in the U.S. -- call for greater protections, particularly among children who have thinner skulls and ears than adult cellphone users.

Volkow's study was conducted between Jan. 1 and Dec. 31, 2009 and included 47 participants.

The researchers found that metabolism in the brain region closest to the antenna was 7 percent higher when exposed to cellphone use.

"These results provide evidence that the human brain is sensitive to the effects of RF-EMFs from acute cell phone exposures," the researchers write.

But they are quick to note: "Results of this study provide evidence that acute cell phone exposure affects brain metabolic activity. However, these results provide no information as to their relevance regarding potential carcinogenic effects (or lack of such effects) from chronic cell phone use."

And the authors encouraged further study.

Louis Slesin, editor of Microwave News, said the study will lead to more questions about the effects low-frequency radiation can have on body tissue. Studies so far have been inconclusive but many researchers have warned about potentially harmful affects on long-term users and youth.

"Whether these short-term changes will lead to health consequences (and what they might be) is far from clear -- though Volkow already has preliminary indications of a long-term effect," Slesin wrote. "Importantly, this new finding upsets the current orthodoxy because
such low-levels EMF effects are thought to be impossible."

Thank you, Washington Post, for giving a fair description of this study. This is an important, high-level scientist, finding something that the cellphone industry has pretty much been denying could exist, despite the outcomes of several independent studies already: cell phone radiation is capable of changing biological processes in the brain, and it does not have to be high intensity to do it.

There will be much dancing around this, and much fog thrown over it by financially interested parties, but the wise consumer will take heed. The FCC exposure limits are not designed to protect the public from such low-level effects, should they cause problems over time.

I'm not quite sure whether or how much danger there is, with cell phone (other than attaching one to your ear while driving a 2 ton vehicle), but this report certainly should prompt further, serious study.

On the other hand beginning the report with "The brain is very important" seems to not be the best path. Does she think that anyone doesn't think that the brain is important? I think that notion went out the window a number of centuries ago.

Good article. I have been studying/researching the impacts of using Cell phones for the last 10 years. This article sums up the inconclusive results that industry and government are providing. IF there isn't any problem with cell phones and their usage, why not publish the facts and findings unless...

Why is it that the media pick up on the inconclusive studies that speculate that there may be a link to cancer, but they ignore the scientific studies like this one that conclude there is no link? I suppose alarmist stories sell more papers and generate more clicks.

Can they say later that the brain will function smarter and faster after being exposed to it constantly for a long time? Or, will there be an uncontrolled lesser usage of the brain without one's knowledge after prolonged exposure?

Is that "increased brain glucose metabolism" protect or destroy brain function?
It's either good, bad, or no relation, Right?

For more on this topic, a new book - Disconnect by Devra Davis - exhaustively reviews research to date on the effects of cellphone radiation on adults and children. As you'll see in this blog post, Davis convinced me to err on the side of caution: http://bit.ly/gssChe

Now it's also true that an hour's work on splitting firewood will result in blisters, which are painful and tissue-damaging but the bad results go away with further repetitions, with some attendant skin-toughening residue, which in fact improves resilience to further blistering. So the existence of a short-term effect is a fact without any value loading until we get some data on (i) the cumulative or transient nature of the effects AND (ii) net bad or net good results. The studies we do have on heavy long-term users do not show any large net bad effects, though these studies need to be better controlled. This is not yet remotely like the situation with heavy smokers or cyclists, where there is some justification for saving people from their own bad habits by imposing restrictions or defense devices.

I find it strange that the study by Institute of Occupational Medicine in Edinburgh and Drexel University in Philadelphia, which was published in January in a little known magazine was reported by news organizations one day before this study was released. Anything to keep us confused.Cellphones and the constant human interactions with electromagnetic radiation is dangerous.

I would not jump to conclusions. Have a look at this article: http://www.theepochtimes.com/n2/science/cell-phone-exposure-brain-cancer-risk-not-increased-but-metabolism-is-51842.html which is supposedly also a good study. Also, I find it personally very cumbersome to hold a phone to my head at all times. Why not use the tools and gadgets that make life easier and keep that phone where it belongs (pocket, cradle, charger, etc). Handsfree is a good thing.

From the study: Conclusions in healthy participants and compared with no exposure, 50-minute cell phone exposure was associated with increased brain glucose metabolism in the region closest to the antenna. This finding is of unknown clinical significance.

The study results, in a word, useless. The study did not describe the cell phones used, their form factor, the type of antenna, the cell network used, their frequencies, nor why 50-mins was used as their standard. Besides, the part of the brain nearest the antenna is associated with, um, hearing, so wouldn't you expect to see more activity there ?! But that wasn't discussed. Very poorly planned study with equally poor results.

They ALL do it. When will we learn? The first line of defense of profiteering without consideration for the consequences to the public is for coporations to try to prevent real information from being published in media outlets. The second line of defense of the corporations is to publish disinformation. The third line of corporations' defense is to litigate any fine print item until decades pass by while their PROFITS MOUNT. The fourth line of defense is to use one-tenth of one percent of their eventual profits to settle all the court cases. WHEN WILL WE LEARN???

I have been keeping track of these studies ever since the one by the Swedes in the late 1990's. As with most of these studies, the methodology is subjective. At worst, this study says that specific Samsung phones may influence elevated glucose levels, nothing more. Glucose is a naturally occurring molecule in the brain used when the brain needs energy.

At best, this may suggest the elevated glucose could be caused by the increased use of the ear while listening.

A more comprehensive objective study must be made with better controls. I recommend a special RF device in the shape of a helmet be made which can imitate various carrier frequencies. This helmet would have several transmitters embedded which can then repeatedly confirm that RF signals do have an effect. By modulating the frequencies and amplitude, one can determine which frequencies have any or no impacts. It is possible that certain RF may resonate molecules in the brain. However none of these questions are even close to being answered by this study. Again, the void of understanding is quickly filled by fear.

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